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# init(uuid:qualifierData:)

Creates an entity identifier with the given UUID and qualifier data.

```
init?(uuid: UUID, qualifierData: Data)
```

## Parameters

`uuid`

The UUID to use for this identifier.

`qualifierData`

The data to distinguish entities that otherwise share the same UUID.
Must be exactly eight bytes; any other length causes this initializer to return `nil`.

## Return Value

A new identifier, or `nil` if `qualifierData` is not exactly eight bytes long.

---

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